Apparatus and method for unwinding a filamentary material



June 24, 1969 G. w. TOOMEY APPARATUS AND METHOD FOR UNWIlNDING A FILAMENTARY, MATERIAL Filed Oct. 26, "1967' Sh eet FIG.|

' n 4;19s9 A G. w. TOOMEY-, 3,451,205

APPARATUS AND METHOD FOR UNWINDING A FILAMENTARY MATERIAL Filed Oct. 26, "1967 A Sheet 2 of s June 24, 1969 G. w. TOOMEY I APPARATUS AND METHOD FOR UNWINDING A FILAMENTARY MATERIAL Filed on. 26, 1967 Sheet F IGS United States Patent US. Cl. 5718 25 Claims ABSTRACT OF THE DISCLOSURE An apparatus for unwinding a filamentary material from a reel of the material and which comprises, disposed coaxially with the reel, a rotationally balanced member rotatable relatively to the reel and resiliently carrying, at a radial extremity of the member, guide means for guiding the material after it has left the reel, and a smoothly convex guiding surface continuous about the axis of the reel and disposed between said member and the reel to maintain the material free of the reel rims.

BACKGROUND OF THE INVENTION This invention relates to apparatus for and a method of unwinding wire or other filamentary maerial, and is applicable, for example, to the unwinding of wire from a reel and thereafter spiralling the wire about an insulating core and also to the unwinding of a wire from a reel and the rewinding of that wire onto a further reel, a bobbin or a coil former.

We are aware of an apparatus for the forming of a coiled :wire conductor upon an insulating core which comprises, mounted coaxially with the reel of wire, a rotationally balanced member comprising a rigid structure carrying at a radial extremity a pulley for guiding the wire drawn from the reel and having depending therefrom and integral therewith a rigid portion carrying at its free end a further pulley for maintaining the wire free of the reel rims. Such apparatus could also be used merely for unwinding Wire from a reel and rewinding it onto a further reel. The problem arises with this apparatus that its speed of rotation is limited. If the speed of rotation increases above a certain value the rigid structure buckles and/or the wire breaks.

SUMMARY In accordance with one aspect of the present invention, there is provided an apparatus for unwinding fila mentary material from a reel of the material and comprising a rotationally balanced member mounted for rotation about the axis of and relatively to said reel, and guide means carried by said member for guiding said material from said reel whilst conveying it about said axis relatively to said reel, and wherein the improvement comprises a guide having a smooth convex guiding surface continuous about said axis and disposed to maintain said material free of the rims of said reel as said material travels from the reel along a smoothly curved path which, as considered in the axial direction of said reel, extends past said guiding surface to and beyond the guide means.

In accordance with a second aspect of the present in- Patented June 24, 1969 ice vention, there is provided a method of unwinding filamentary material from a reel, comprising the step of drawing the material from the reel to guide means carried by a rotationally balanced member caused to rotate about the axis of and relatively to said reel by the force applied to the guide means by the drawing of the material, wherein the improvement comprises guiding the said material along a smoothly curved path to and beyond said guide means past a smooth convex guiding surface which is continuous about said axis and which is disposed at a region axially between said material on said reel and said guide means to maintain said material free of the rims of said reel.

It is of advantage for said rotatable member to be flexible at least to such an extent that the free end of its arm can be rotated easily by hand, in a plane parallel to the axis and at right angles to the direction in which the arm extends when not flexed, to produce a circular movement of said arm of at least one-half an inch radius at a point approximately 3 /2 inches from the axis and without permanent deformation. If one wishes to use a rotatable member having a total radius of less than 3 /2 inches, then this relationship of dimensions must be scaled down accordingly.

It is of especial advantage, particularly when the apparatus is to be used to unwind wire having a crosssectional area which is at least as small as that of 28 SWG wire, to make the rotatable member very light, e.g. no heavier than 20 grammes. This enables one to achieve high rotational speeds for the rotatable member such as at least 5,000 rpm. In one practical case, speeds in the range from 5,000 r.p.m. to 10,000 rpm. have been achieved without breakage with a member weighing approximately 10 grammes.

It is also considered advantageous for the radius at which the guide means will guide wire to be no less than a radius substantially equal to the maximum radius at which said guiding surface exists.

The curvature of the guiding surface is preferably such that an imaginary circle of radius no less than one-eighth of an inch, and advantageously no less than one-quarter of an inch, can be positioned tangentially at any point or region at the concave side of a curve having the axial cross-sectional form of the guiding surface. Preferably the guiding surface has a,convex extent, as considered in a direction in any plane containing the said axis, of at least one-quarter of an inch and advantageous of at least one-half of an inch.

The guide means is advantageously a wire loop or eyelet so that the guided wire is positively prevented from becoming free of the arm during operation and so that the air resistance of the rotatable member can be made as small as possible. In particular, it is noted that the lower the air resistance the higher the speed that can be obtained without wire breakage.

For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

FIGURE 1 is a diagram of a machine for producing a coiled-Wire conductor suitable for electric blankets;

FIGURE 2 is a plan view of the unwinding apparatus used in the machine of FIGURE 1;

FIGURE 3 is a cross-section on the AA of FIG- URE 2;

FIGURE 4 is a diagram of a machine for winding wire from one reel onto a further reel; and

FIGURE is a diagram of a further form of machine for forming coiled-wire conductors.

FIGURE 1 is a diagram of a machine for producing a coiled-wire conductor 1 consisting of a core 2 of nonconductive thread on which is coiled a conductor 3 of, for example, nickel chrome wire, copper nickel wire, Phosphor-bronze wire, cadmium copper wire or pure nickel wire of cross-sectional area at least as small as that of 28 SWG Wire. The wire 3 is coiled on the core 2 with, for exam le, 30 threads per inch, and this number can be varied with the illustrated apparatus. The core 2 extends from a reel 4 through a passage extending through the installation and runs several times over two sets of six pulleys 5 and 6 and then onto a finishedproduct reel 7. The reel 7 is driven from an electric motor 8 through a pulley 9 to pull the core 2 from its reel 4.

The wire 3 is taken from a reel 10, in this case a B.S.C. 15 reel with a rim diameter of approximately 3% inches and a height of approximately 3% inches. The wire 3 extends from the reel 10 past the smoothly convex guiding surface, continuous about the axis of the reel, of a guide 11 of hard wearing low friction material such as may be found among synthetic resins, for example a polyamide impregnated with an appropriate lubricant. The wire 3 extends from the guiding surface of the guide 11 through an eyelet 12 carried at the free end of an arm 13 of a rotationally balanced member 14 mounted for rotation with respect to a stub shaft 15 driven with the reel 10 and the guide 11. The wire 3 extends from the eyelet 12 to the upper surface of a domeshaped portion 16 through an aperture in which the core 2 extends to the set of rollers 5.

The reel 10, the guide 11 and the stub shaft 15 are rotated at at least 5,000 r.p.m. whilst the core 2 is driven therethrough at, say, four and a half yards per minute, the result being that the wire 3, whilst being drawn upwardly with the core 2, is spun around the core 2 and thus forms a wire spiral thereon. The member 14 also rotates but at a speed slightly slower than that of the reel, say one or two r.p.m. slower, as is necessary to cause unwinding of the wire 3 from the reel 8. At these high speeds the arm 13 flexes considerably but without permanent deformation and without wire breakage.

The reel 10, the guide 11 and the stub shaft 15 are driven by a motor 17 through a pulley system 18 and a hollow spindle 19, the spindle 19 being rotationally supported by a bearing 20 carried by the frame 21 of the machine. As will be described more fully hereinafter, the spindle 19 is secured to the stub shaft 15 to clamp the guide 11 and reel 10 between the stub shaft and a flange 22 secured to the spindle shaft 19. v

The coiled-wire conductor produced by such an installation is advantageously used for electric blankets, but whatever its intended use it is normally highly desirable for the resistance per unit length of the resultant conductor to be constant. To achieve this result automatically, a first contact 23 is attached to the first pulley of the set of six pulleys 5 and a second contact 24 to the last pulley of the set of six pulleys 6 whereby there will always exist between the contacts a constant length, for example three yards, of the coiled conductor. A servomechanism system 25 is provided to sense the resistance between these contacts continuously and to eifect appropriate control of the speed of the motor 8 and thus of the core 2 to maintain this resistance constant.

The apparatus consisting of the parts 11, 12, 13, 14, 15 and 16 will now be described in more detail with reference to FIGURES 2 and 3. The member 11 of a lubricant-impregnated poylamide contains a circular shaped recess 26, to receive the rim of the reel 10, and also contains a central bore 27 through which the core 2 is to extend. The smoothly convex effective guiding surface of the guide 11 is indicated by a heavy line at 28. It will be seen that the guide 11 prevents the wire 3 from coming into contact with the reel rim. In this case the length of the line 28 is approximately three quarters of an inch and the line has a curvature such that a circle of one inch radius can rest tangentially at the concave side of the line The stub shaft 15, which is of metal, is bored out at 29 to accept the hollow spindle shaft 19 (FIGURE 1) by which the apparatus is'to be driven to rotate in either direction, and to which spindle shaft the stub shaft is secured by a screw 30. The stub shaft also contains a bore 31 through which the core 2 will extend. The dome portion 16 is provided at the upper free end of the stub shaft 15 and may be made integral with or separate from the stub shaft 15. In operation, the stub shaft 15 will be clamped by means of the aforesaid spindle shaft 19 to the member 11 and to the reel 10 to rotate therewith. Thus, the hollow spindle shaft 19 through which the core will extend is passed through the reel until the reel rests on the flange 22 secured to the shaft 19. A first nut is then threaded on the spindle shaft to clamp the reel between the nut and the flange. The spindle shaft is then passed through the guide 11 and is secured in the recess 29 of the stub shaft 15 so as to clamp the guide 11 between the reel and the shaft 15.

The member 14 is freely rotatably mounted on the stub shaft 15 by means of a bush 32, of a light material such as a synthetic resin e.g. a polyamide, located between a retaining collar 33 secured to the stub shaft 15 and a washer 34 urged against the lower side of the bush 32 by a spring 35. The arms 13, of stainless steel wire, spring steel or other high tensile material, are embedded in and extend from the bush 32 and carry at their free ends, in wire loops, eyelets 12 of a hard wearing ceramic, such as Sintox.

In the specific example illustrated in FIGURES 2 and 3 the following dimensions have been adopted:

Diameter of the guide 11.4%"

Height of the guide 11.-1%

Height of the arms 13 above the upper surface of the guide 11.l

Diameter of the member 14 between the centres of the eyelets 10.-7%"

Diameter of the arms 13.

Axial height of the bush 32.-%

Diameter of the bush 32.1%

Weight of the member 14.-9.6 grammes Flexibility of member 14.Enabling each eyelet 12 to be moved easily by hand in a circle of radius /2" in a plane at right angles to the direction of extension of the arms.

With an apparatus of these dimensions, it has been possible to wind wire of 28 SWG and finer gauge with the reel 10 and member 14 rotating in the range from 5,000 r.p.m. to 10,000 r.p.m. without wire breakage. It is to be noted that the area of the member 14, especially that of the outer parts of the member, on which air will be incident to oppose rotation of the member, is very small. This feature assists in the attainment of the high operating speeds because the lower the air resistance the lower is the resultant tension in the wire.

It is also to be noted that because the eyelet 12 is at that side of a plane at right angles to the axis and cutting the guiding surface 28 remote from the reel and because the guiding surface can maintain the wire away from the reel rims, the wire maintains a smoothly curved path from the reel to well beyond the eyelet. There are thus no sharp changes of direction in the path such as might limit the operating speed.

The dimensions of a suitable apparatus depend to some extent upon the dimensions of the reel 10 which is to be used and upon the size of Wire to be unwound. Furthermore it is to be noted that this apparatus can be used with its axis vertical, horizontal or with any other orientation. It will also be apparent that other alterations can be made, for example the bush 32 can be held spaced from the guide 11 by a spacer rather than by a spring. In addition a wire loop at the ends of the arms 13 may be all that is necessary to guide the wire in some applications. In some cases, when the wire to be unwound is relatively thick and the speed of rotation is accordingly lower than that given above for the specific example, a guide wheel may be provided at the free end of each arm as guide means for the wire. The air resistance provided by such a wheel may in such a case not be an important consideration. In addition materials other than those already specified are suitable, such as wood or metal for the guide 11. Furthermore, the member 14 can have any number of arms as long as it is substantially balanced about its axis.

FIGURE 4 shows a further application of the apparatus of FIGURES 2 and 3. In this case, wire is unwound from the reel 10, which is held stationary together with the guide 11 and the stub shaft 15, whilst the wire is drawn from the reel over the guide 11, through the eyelet 12 to an axially arranged pulley 36 padded with felt 37. The wire 3 extends from the pulley 36 over pulleys 38 and 39 to a further reel 40 on which the wire is rewound. The pulleys 38 and 39 are mounted on an arm 41 which is pivotally mounted and spring biased to the position illustrated. The wire 3 will be drawn from the reel 10 by the pull on the wire caused by rotation of the reel 40, thereby producing rotation of the member 14 to unwind the wire. As in the previous case, the wire can be unwound rapidly, with the member 14 rotated at 5,000 rpm. or more without wire breakage.

FIGURE 5 shows a modification of FIGURE 1 in which, alternatively or in addition to the domed member 16 of FIGURE 1, there is a domed member 42 acting to prevent the wire 3 from flying too far from the member 14. Here the member 14 is retained against collar 33 by a spring washer 43.

I claim:

1. An apparatus for unwinding filamentary material from a reel of the material and comprising a rotationally balanced member mounted for rotation about the axis of and relatively to said reel, and guide means carried by said member for guiding said material from said reel whilst conveying it about said axis relatively to said reel, and wherein the movement comprises a guide having a smooth convex guiding surface continuous about said axis and disposed to maintain said material free of the rims of said reel as said material travels from the reel along a smoothly curved path which, as considered in the axial direction of said reel, extends past said guiding surface to and beyond the guide means.

2; An apparatus as claimed in claim 1, wherein said guide means are mounted so as to be capable of substantial resilient movement relatively to said axis in all directions in a plane parallel to said axis and cutting said guide means.

3. An apparatus as claimed in claim 2, wherein said member compirses an arm of flexible material to provide for said resilient movement, by which arm said guide means is carried.

4. An apparatus as claimed in claim 3, wherein said arm is of wire.

5. An apparatus as claimed in claim 3, wherein said flexible material is such that a length of it of about three and a half inches can be held against movement at one end and its other end moved in a circle of a half an inch radius without permanent deformation of said flexible material.

6. An apparatus as claimed in claim 1, wherein the rotatable member weighs no more than twenty grammes.

7. An apparatus as claimed in claim 6, wherein said rotatable member weighs about ten grammes.

8. An apparatus as claimed in claim 1, wherein said guide means are disposed so as to guide said filamentary material at a distance from said axis greater than the greatest radius of said guiding surface.

9. An apparatus as claimed in claim 1, wherein the guiding surface has at no point a radius of curvature less than one eighth of an inch.

10. An apparatus as claimed in claim 9, wherein said radius is not less than one quarter of an inch.

11. An apparatus as claimed in claim 1, wherein the guiding surface has an effective extent in any plane containing said axis of at least a quarter of an inch.

12. An apparatus as claimed in claim 11, wherein said extent is at least one half of an inch.

13. An apparatus as claimed in claim 1, wherein said guide is of a hard wearing, low friction, material.

14. An apparatus as claimed in claim 13, wherein the guide is of a polyamide resin.

15. An apparatus as claimed in claim 14, wherein said guide is impregnated with a friction reducing impregnant.

16. An apparatus as claimed in claim 1, wherein said guide means is apertured so as positively to prevent said filamentary material from becoming free of said arm.

17. An apparatus as claimed in claim 16, wherein said guide means comprises an eyelet.

18. An apparatus as claimed in claim 16, wherein said guide means comprises a wire loop.

19. An apparatus as claimed in claim 1, wherein, for rotational balance, said rotatable member has more than one said arm.

20. An apparatus as claimed in claim 1 and further comprising a domed member on said axis at that side of said rotatable member remote from said guide with its apex pointing axially away from said rotatable member to maintain said filamentary material out of contact with the central region of said rotatable member.

21. An apparatus as claimed inclaim 1 and further comprising a passage extending axially of the apparatus to receive a moving filamentary core whereby said filamentary material can be coiled about said core.

22. An apparatus for unwinding filamentary material from a reel of said material and comprising: support means for supporting said reel; a guide having a smooth convex guiding surface, continuous about an axis upon which said supporting means can support the axis of said reel, for maintaining said material clear of the reel rims whilst said material is being unwound; a rotationally balanced member mounted for rotation about said axis at that side of said guide opposite to the side at which said reel is to be supported; and guide means for said filamentary material carried resiliently by said member at a region directly radially outwardly of the axial region at which said member is rotatably mounted, whereby said filamentary material can be guided about said axis relatively to said reel whilst at the same time being drawn with an axial component of velocity upon a smoothly curved path extending from said reel and past said guiding surface to and beyond said guide means.

23. A machine for unwinding filamentary material from a reel of the material and comprising: reel support means for supporting a reel with its axis extending along an axis of the machine; a rotationally balanced member mounted for rotation relatively to the reel about said axis; drive means operable to draw the material from the reel with an axial component of velocity; guide means carried by said member for guiding said material drawn from said reel whereby said material is unwound from said reel by virtue of relative rotation between said member and said reel; and a guide disposed so as to be between said member and said reel and having a smooth convex guiding surface continuous about said axis for maintaining said material clear of the reel rims as it is drawn from the reel with an axial component of velocity past the guiding surfaceand then through said guide means along a smoothly curved path.

24. A machine according to claim 23 and further comprising: a hollow driving spindle shaft coupled axially to said reel supporting means; second drive means 0perable to rotate the spindle shaft and with it said reel; a passage extending axially through said shaft, said reel, said guide and said rotatable member; and means for supporting a reel of core material at that end of said spindle shaft remote from said guide and said rotatable member whereby said first-mentioned drive means are capable of drawing said core material through said reel, said guide and said rotatable member at the same time as drawing said filamentary material, whereby said filamentary material will be coiled around said core material.

25. A method of unwinding filamentary material from a reel, comprising the step of drawing the material from the reel to guide means carried by a rotationally balanced member caused to rotatae about the axis of and relatively to said reel by the force applied to the guide means by the drawing of the material, wherein the improvement comprises guiding the said material along a smoothly curved path to and beyond said guide means past a smooth convex guiding surface which is continuous about said axis and which is disposed at a region axially between said material on said reel and said guide means to maintain said material free of the rims of said reel.

References Cited UNITED STATES PATENTS 1,949,484 3/1934 Mayer 5718 2,220,006 10/1940 Walsh et al 57-l8 2,237,062 4/ 1951 Schlums 57l8 2,365,660 12/1944 Winslow 57-116 2,659,108 11/1953 Bradley 242-457 XR 2,831,313, 4/1958 Burns et a1. 2,466,797 4/ 1949 Egge 57--18 XR 2,947,136 1 8/1960 Arridge.

DONALD E. WATKINS, Primary Examiner.

US. Cl. X.R. 57--116, 156 

